The present invention relates to a brake disc, in particular for motor vehicles, that is non-rotatably and axially displaceably connected with a hub to be braked.
Brake discs of this type are required for disc brakes with an actuation device arranged on one side of the brake disc, only, which, by means of a displaceable friction lining on one side of the brake disc actuated by the actuation device, will press the brake disc against an undisplaceably arranged friction pad on the other side of the brake disc. In such brake discs, there exist special requirements with regard to the connection between the brake disc and the hub. This connection has to ensure an easy axial displaceability of the brake disc, on the one hand, yet serve for the transmission of high torque forces, on the other hand.
In German Utility Pat. (Dt-GM) No. 7,012,103 there is disclosed an axially displaceable brake disc having radially extending projections which project into recesses of the hub and come into mesh with radially aligned guide surfaces of the hub. Further, leaf springs are provided opposite the hub for the centering of the brake disc, the springs being connected at the hub and acting on outside surfaces of the projections which are cylindrical in respect to the axis of rotation of the brake disc.
This known brake disc is disadvantageous in that in case of small torques there will be an engagement of the torque transmission surfaces at the projections and the hub, and, thus, any axial displacement of the brake disc with respect to the hub is possible only against the frictional drag caused by the transmitted torque. Due to the influence of dirt, the frictional drag may develop such proportions that the displaceability of the brake disc will be impaired considerably and the brake shoes arranged on both sides of the brake disc will be exposed to uneven wear.